2022-2023年考博英语-江苏大学模拟考试题（含答案解析）第42期

2022-2023年考博英语-江苏大学模拟考试题（含答案解析）1. 翻译题One of the most important and effective uses of language is the emotional. It is also, of course, wholly legitimate. We do not talk only in order to reason or to inform. We have to make love and quarrel, to propitiate and pardon, to rebuke, to console, intercede, and arouse. “He that complains,” said Johnson, “acts like a man, like a social being.” The real objection lies not against the language of emotion as such, but against language which, being in reality emotional, masqueradeswhether by plain hypocrisy or subtle self-deceitas being something else.【答案】语言最重要、最有效的一种用途就是表达感情。这当然也完全是合情合理的。我们说话不止是为了讲道理、说事情。我们还要表达爱情、与人争吵、劝诫抚慰、宽恕原谅、调解、激发他人。约翰逊说过：“会抱怨的人行动起来才像一个人，才像一个社会的人。”我们真正要反对的并不是这种表达感情的语言，而是那种实质是表达感情，但却通过十足的虚伪或者是巧妙的自欺，伪装成别的东西的语言。2. 单选题Russias government has, in effect, defaulted on its debt; its economic predicament worsens by the day.问题1选项A.dangerB.depressionC.slumpD.crisis【答案】D【解析】【选项释义】A. danger危险；风险 B. depression抑郁；不景气C. slump（销售量、价格、价值等的）骤降；萧条期 D. crisis危机；危难时刻【考查点】名词辨析。【解题思路】根据前半句句意“俄罗斯政府已经拖欠债务”，结合关键词worsen可推知，economic predicament是指经济危机，predicament在句中指“危机，困境”的意思，D项词义与之相近，故该题选择D项。【干扰项排除】A、B、C项不符合划线单词词义。【句意】事实上，俄罗斯政府已经拖欠债务；它的经济困境日益恶化。3. 单选题Its no good _ him. He is always indifferent towards others matters.问题1选项A.to turn toB.turning toC.turn toD.turned to【答案】B【解析】【选项释义】A. to turn to求助于 B. turning to求助于C. turn to求助于 D. turned to求助于【考查点】固定搭配。【解题思路】由no good可知，its no good doing sth.是固定搭配，表示“做某事是没用的”，故该题选择B项。【干扰项排除】A、C、D项不符合固定搭配。【句意】求助于他是没有用的。他对别人的事总是漠不关心。4. 单选题The talks have become _ with both sides refusing to compromise any further.问题1选项A.irrationalB.irreconcilableC.irreparableD.irreplaceable【答案】B【解析】【选项释义】A. irrational不合逻辑的；没有道理的 B. irreconcilable矛盾的；不可调和的C. irreparable无法弥补的；不能修复的 D. irreplaceable（因贵重或独特）不能替代的【考查点】形容词辨析。【解题思路】根据关键信息with both sides refusing to compromise any further（双方都拒绝进一步妥协）可知，这次谈判是不可调和的，B项符合句意，故该题选择B项。【干扰项排除】A、C、D项不符合句意。【句意】由于双方都拒绝进一步妥协，谈判变得不可调和。5. 单选题David is trying to get that promotion by hook or by crook; he even spread rumors defaming other candidates.问题1选项A.scaringB.smearingC.squashingD.startling【答案】B【解析】【选项释义】A. scaring使害怕；使恐惧 B. smearing诽谤；弄脏C. squashing挤压 D. startling使惊吓；使吓一跳【考查点】动词辨析。【解题思路】根据关键信息spread rumors（散发谣言）可推知，defaming是指“诽谤”的意思，B项词义与之相近，故该题选择B项。【干扰项排除】A、C、D项词义不符合句中所选词汇。【句意】大卫为了得到提升不择手段；他甚至散布诽谤其他候选人的谣言。6. 单选题The tests show the earlier in life a person hears a sound the longer it is _.问题1选项A.retainedB.preservedC.remainedD.reserved【答案】A【解析】【选项释义】A. retained保留 B. preserved保护C. remained保持；停留 D. reserved保留；贮备【考查点】动词辨析。【解题思路】分析句子，it指的是sound，根据longer可知，此处是说声音保留的时间越长，retain的牛津释义是to continue to hold（继续保持），该题选择A项符合句意。【干扰项排除】B项不符合句意；C项侧重保持一种状态或条件不变；D项侧重保留某种权利。【句意】测试表明，一个人在生活中听到声音的越早，它保留的时间就越长。7. 单选题Since the couple could not _ their difference, they decided to get a divorce.问题1选项A.reconcileB.complyC.coincideD.resign【答案】A【解析】【选项释义】A. reconcile调和；使和解 B. comply遵从；服从C. coincide同时发生 D. resign辞职；辞去（某职务）【考查点】动词辨析。【解题思路】根据后半句“他们决定离婚”可推知，他们的分歧没有和解，空格处表示“和解”符合句意，故该题选择A项恰当。【干扰项排除】B、C、D项不符合句意。【句意】由于这对夫妇的分歧无法得到和解，他们决定离婚。8. 单选题The market had been priced at historic highs relative to benchmarks like corporate profits and individuals.问题1选项A.standardsB.touchstonesC.hallmarksD.norms【答案】B【解析】【选项释义】A. standards标准；水平 B. touchstones试金石；检验标准C. hallmarks特征；特点 D. norms行为标准【考查点】名词辨析。【解题思路】benchmark本意是“基准”，由relative to（相对于）可知，benchmark在这是指用已知的东西作标准，与其他事物进行比较，而touchstone也可指作为判断第二件事的测试或标准，含有比较的意味，故B项词义与之相近，故该题选择B项。【干扰项排除】A项指公认的、尤指可被接受的社会各个方面一般的标准、水准、度量衡标准、衡量品质、才度、价值、道德、规则、原则等的标准；C项不符合划线单词词义；D项指在特定社会中被认为正常的行为方式或组织期望达到的官方标准或水平。【句意】相对于企业利润和个人等基准，股市的定价一直处于历史高位。9. 不定项选择题As Gilbert White, Darwin, and others observed long ago, all species appear to have the innate capacity to increase their numbers from generation to generation. The task for ecologists is to untangle the environmental and biological factors that hold this intrinsic capacity for population growth in check over the long run. The great variety of dynamic behaviors exhibited by different population makes this task more difficult: some populations remain roughly constant from year to year; others exhibit regular cycles of abundance and scarcity; still others vary wildly, with outbreaks and crashes that are in some cases plainly correlated with the weather, and in other cases not.To impose some order on this kaleidoscope of patterns, one school of thought proposes dividing populations into two groups. These ecologists posit that the relatively steady populations have density-dependent growth parameters; that is, rates of birth, death, and migration which depend strongly on population density. The highly varying populations have density-independent growth parameters, with vital rates buffeted by environmental events; these rates fluctuate in a way that is wholly independent of population density.This dichotomy has its uses, but it can cause problems if taken too literally. For one thing, no population can be driven entirely by density-independent factors all the time. No matter how severely or unpredictably birth, death, and migration rates may be fluctuating around their long-term averages, if there were no density-dependent effects, the population would, in the long run, either increase or decrease without bound (barring a miracle by which gains and losses canceled exactly). Put another way, it may be that on average 99 percent of all deaths in a population arise from density-independent causes, and only one percent from factors varying with density. The factors making up the one percent may seem unimportant, and their cause may be correspondingly hard to determine. Yet, whether recognized or not, they will usually determine the long-term average population density.In order to understand the nature of the ecologists investigation, we may think of the density-dependent effects on growth parameters as the signal ecologists are trying to isolate and interpret, one that tends to make the population increase from relatively low values or decrease from relatively high ones, while the density-independent effects act to produce noise in the population dynamics. For populations that remain relatively constant, or that oscillate around repeated cycles, the signal can be fairly easily characterized and its effects described, even though the causative biological mechanism may remain unknown. For irregularly fluctuating populations, we are likely to have too few observations to have any hope of extracting the signal from the overwhelming noise. But it now seems clear that all populations are regulated by a mixture of density-dependent and density-independent effects in varying proportions.1. The author of the text is primarily concerned with _.2. It can be inferred from the text that the author considers the dichotomy discussed to be _.3. According to the text, all of the following behaviors have been exhibited by different populations EXCEPT _.4. The discussion concerning population in the third paragraph serves primarily to _.5. In the text, the author does all of the following EXCEPT _.问题1选项A.discussing two categories of factors that control population growth and assessing their relative importanceB.describing how growth rates in natural populations fluctuate over time and explaining why these changes occurC.proposing a hypothesis concerning population size and suggesting ways to test itD.posing a fundamental question about environmental factors in population growth and presenting some currently accepted answer问题2选项A.applicable only to erratically fluctuating populationsB.instrumental, but only if its limitations are recognizedC.dangerously misleading in most circumstancesD.a complete and sufficient way to account for observed phenomena问题3选项A.roughly constant population levels from year to yearB.regular cycles of increases and decreases in numbersC.erratic increases in numbers correlated with the weatherD.unchecked increases in numbers over many generations问题4选项A.demonstrate the difficulties ecologists face in studying density-dependent factors limiting population growthB.advocate more rigorous study of density-dependent factors in population growthC.prove that the death rates of any population are never entirely density-independentD.underline the importance of even small density-dependent factors in regulating long-term population densities问题5选项A.cite the views of other biologistsB.define a basic problem that the text addressesC.present conceptual categories used by other biologistsD.describe the results of a particular study【答案】第1题:A第2题:B第3题:D第4题:D第5题:D【解析】1.【选项释义】1. The author of the text is primarily concerned with _. 1. 本文的作者主要关注_。A. discussing two categories of factors that control population growth and assessing their relative importance A. 讨论控制人口增长的两类因素，并评估它们的相对重要性B. describing how growth rates in natural populations fluctuate over time and explaining why these changes occur B. 描述自然种群的增长率如何随时间波动，并解释为什么会发生这些变化C. proposing a hypothesis concerning population size and suggesting ways to test it C. 提出关于种群规模的假设并提出检验方法D. posing a fundamental question about environmental factors in population growth and presenting some currently accepted answer D. 提出一个关于人口增长中的环境因素的基本问题，并给出一些目前被接受的答案【考查点】主旨大意题。【解题思路】文章首先提出物种增长的现象，随即提出二分法并对其进行讨论，最后对这个二分法进行评估，因此在这篇文章中，作者主要关注的是讨论控制人口增长的两类因素以及他们的重要性，所以A项“讨论控制人口增长的两类因素，并评估它们的相对重要性”符合题意。【干扰项排除】B项“描述自然种群的增长率如何随时间波动，并解释为什么会发生这些变化”、C项“提出关于种群规模的假设并提出检验方法”和D项“提出一个关于人口增长中的环境因素的基本问题，并给出一些目前被接受的答案”都是文章中的一部分，不够全面，这三项属于以偏概全。2.【选项释义】2. It can be inferred from the text that the author considers the dichotomy discussed to be _. 2. 从文中可以推断，作者认为讨论的二分法_。A. applicable only to erratically fluctuating populations A. 只适用于不稳定波动的人口B. instrumental, but only if its limitations are recognized B. 有用的，但前提是它的局限性被认识到C. dangerously misleading in most circumstances C. 在大多数情况下都是危险的误导D. a complete and sufficient way to account for observed phenomena D. 解释观察到的现象的一种完整而充分的方法【考查点】推理判断题。【解题思路】根据关键词dichotomy定位至第三段首句“这种二分法有它的用途，但如果从字面上理解，就会产生问题（but it can cause problems if taken too literally）”，其中二分法指的是第二段提到的两类种群，即相对稳定的种群和高度变化的种群，第二段讨论了这两种种群的不同用途，说明二分法是有用的；然后第三段首句却提到but it can cause problems if taken too literally（但如果从字面上理解，就会产生问题），可以看出，二分法有其局限性，所以B项“有用的，但前提是它的局限性被认识到”符合题意。【干扰项排除】A项“只适用于不稳定波动的人口”表述太绝对，该项属于曲解原文；C项“在大多数情况下都是危险的误导”和D项“解释观察到的现象的一种完整而充分的方法”表述都比较片面，这两项属于以偏概全。3.【选项释义】3. According to the text, all of the following behaviors have been exhibited by different populations EXCEPT _. 3. 根据本文，以下所有的行为都在不同的物种中出现过，除了_。A. roughly constant population levels from year to year A. 每年大致保持恒定的人口水平B. regular cycles of increases and decreases in numbers B. 数字有规律的增加和减少的循环C. erratic increases in numbers correlated with the weather C. 数量的不稳定增长与天气有关D. unchecked increases in numbers over many generations D. 数代人不受制约的增长【考查点】细节事实题。【解题思路】根据首段前两句“正如吉尔伯特怀特、达尔文和其他人很久以前观察到的那样，所有物种（all species）似乎都具有与生俱来的能力，能够一代一代地增加它们的数量。生态学家的任务是理清环境和生物因素，从长远来看，这些因素制约着（in check）人口增长的内在能力”，其中all species对应了题干中的different populations，可知不同的物种都具有能够一代一代地增加它们的数量的能力，但是这种能力受到环境和生物因素的制约，D项“数代人不受制约的增长”中的unchecked与原文不符合，但符合题干，故该题选择D项。【干扰项排除】A项“每年大致保持恒定的人口水平”、B项“数字有规律的增加和减少的循环”和C项“数量的不稳定增长与天气有关”，根据第一段最后一句“不同种群表现出的各种动态行为使得这项任务更加困难：有些种群年复一年大致保持不变；另一些则表现出规律性的丰富性和稀缺性循环；还有一些情况差别很大，疾病的爆发和崩溃在某些情况下与天气密切相关，而在其他情况下则与天气无关”可知，这三项行为都在不同的物种中出现过，故属于反向干扰。4.【选项释义】4. The discussion concerning population in the third paragraph serves primarily to _. 4. 第三段中关于种群的讨论主要是为了_。A. demonstrate the difficulties ecologists face in studying density-dependent factors limiting population growth A. 说明生态学家在研究限制种群增长的密度依赖因素时所面临的困难B. advocate more rigorous study of density-dependent factors in population growth B. 提倡更严格地研究种群增长中密度依赖的因素C. prove that the death rates of any population are never entirely density-independent C. 证明任何种群的死亡率都不是完全与密度无关的D. underline the importance of even small density-dependent factors in regulating long-term population densities D. 强调即使是很小的密度依赖因素在调节长期的种群密度方面的重要性【考查点】推理判断题。【解题思路】首先定位第三段，该段主要陈述density-dependent factors（密度依赖因素），由最后三句“换句话说，种群中平均99%的死亡是由与密度无关的原因引起的，只有1%是随密度变化的因素引起的。构成这1%的因素可能看起来不重要，它们的原因可能相应地难以确定。然而，无论是否被认识到，它们通常将决定长期的平均种群密度。”可知，种群中只有1%的死亡是由密度依赖因素引起，但是这1%的因素通常决定长期的平均种群密度，综合理解可以推断，第三段关于种群的讨论主要是为了强调密度依赖因素在调节种群密度方面的重要性，D项“强调即使是很小的密度依赖因素在调节长期的种群密度方面的重要性”符合题意。【干扰项排除】A项“说明生态学家在研究限制种群增长的密度依赖因素时所面临的困难”在第三段没有依据，该项属于无中生有；B项“提倡更严格地研究种群增长中密度依赖的因素”，该段只是证明了种群增长中密度依赖因素的重要性，但是advocate在该段没有体现，该项属于无中生有；C项“证明任何种群的死亡率都不是完全与密度无关的”并不是第三段讨论种群的重点，该项属于本末倒置。5.【选项释义】5. In the text, the author does all of the following EXCEPT _. 5. 在本文中，作者做了以下所有的事情，除了_。A. cite the views of other biologists A. 引用其他生物学家的观点B. define a basic problem that the text addresses B. 定义文章要解决的一个基本问题C. present conceptual categories used by other biologists C. 介绍其他生物学家使用的概念范畴D. describe the results of a particular study D. 描述一项特定研究的结果【考查点】推理判断题。【解题思路】通读全文可知，本文作者在论述自己的观点时运用了各种写作手段，第一段引用生物学家的观点引出文章主题，第二段介绍其他生态学家所定义的概念，第三段和第四段则是提出二分法需要解决的一个问题，并介绍理解生态学家们所从事的研究的性质的不同方法，只有D项“描述一项特定研究的结果”的写作手法并没有在文中运用，故该题选择D项符合题意。【干扰项排除】A项“引用其他生物学家的观点”在第一段有体现，该段引用了吉尔伯特怀特和达尔文，该项属于反向干扰；B项“定义文章要解决的一个基本问题”在第三段有体现，第一句提到“这种二分法有它的用途，但如果从字面上理解，就会产生问题”，该项属于反向干扰；C项“介绍其他生物学家使用的概念范畴”在第二段有体现，第一句提到“为了给这种千变万化的模式赋予一些秩序，一种思想学派建议将种群分为两类”，该项属于反向干扰。10. 单选题The evil manners would be eradicated root-and-branch due to the forceful action taken by the local government.问题1选项A.exterminatedB.exemplifiedC.renderedD.harbored【答案】A【解析】【选项释义】A. exterminated灭绝；根除 B. exemplified举例说明；例证C. rendered使成为；使变得 D. harbored窝藏，庇护（罪犯等）【考查点】动词辨析。【解题思路】根据关键信息due to the forceful action taken by the local government（由于当地政府的有力措施）和关键词evil manners（不良行为）可知，该句是表示不良行为被有力措施根治，eradicated在这里表示“消除”的意思，故该题选择A项词义恰当。【干扰项排除】B、C、D项词义不符合句中所选词汇。【句意】由于当地政府的有力措施，这种不良行为将被根治。11. 单选题Most environmental _ from climate changes to freshwater and forest habitat losshave become markedly worse.问题1选项A.symptomsB.highlightsC.indicatorsD.symbols【答案】A【解析】【选项释义】A. symptoms症状；征兆 B. highlights最好（或最精彩、最激动人心）的部分C. indicators指示信号 D. symbols象征；符号【考查点】名词辨析。【解题思路】空格后用了破折号，说明破折号的内容是补充解释空格处所要填的名词，根据破折号内的内容“从气候变化到淡水和森林栖息地的丧失”可知，这是环境恶化的征兆，故空格处表示“征兆”，该题选择A项符合句意。【干扰项排除】B、C、D项不符合句意。【句意】大多数环境症状从气候变化到淡水和森林栖息地的丧失已经明显恶化。12. 单选题You may feel exhausted under stressful brainwork, heavy physical labor or panic and disconsolate moods.问题1选项A.pitifulB.cordialC.dismalD.rough【答案】C【解析】【选项释义】A. pitiful令人同情的；可怜的 B. cordial热情友好的；和蔼可亲的C. dismal忧郁的；凄凉的 D. rough粗糙的；不平滑的【考查点】形容词辨析。【解题思路】根据所修饰的名词mood可知，disconsolate是和情绪相关的形容词，根据前文的feel exhausted（感到筋疲力尽）可推断，disconsolate的词义和负面情绪相关，只有C项词义与人本身的负面情绪相关，故该题选择C项。【干扰项排除】A、B、D项词义不符合句中所选词汇。【句意】在紧张的脑力劳动、繁重的体力劳动或恐慌、忧郁的情绪下，你可能会感到精疲力竭。13. 不定项选择题Flight simulator (飞行模拟器) refers to any electronic or mechanical system for training airplane and spacecraft pilots and crew member by simulating fight conditions. The purpose of simulation is not to completely substitute (1) actual fight training but to thoroughly familiarize students with the vehicle (2) before they (3) extensive and possibly dangerous actual flight training. Simulations also is useful for review and for familiarizing pilots with new (4) to existing craft.Two early flight simulators appeared in England within a decade after the first fight of Orville and Wilbur Wright. They were designed to enable pilots to stimulate simple aircraft (5) in three dimensions: nose up or down; left wing high and right low, or vice versa; and (6) to left or right. It took until 1929, however, for a truly effective simulator, the Link Trainer, to appear, devised by Edwin A. Link, a self-educated aviator and inventor from Binghamton, New York. (7), airplane instrumentation had been developed sufficiently to permit “blind” flying on instruments alone, but training pilots to do so involved (8) risk. Link built a model of an airplane cockpit equipped (9) instrument panel and controls that could realistically stimulate all the movements of an airplane. Pilots could use the device for instrument training, manipulating the controls (10) instrument readings so as to maintain straight and level flight or (11) climb or descent with no visual reference (12) any horizon except for the artificial one on the instrument panel. The trainer was modified (13) aircraft technology advanced. Commercial airlines began to use the Link Trainer for pilot training, and the US government began purchasing them in 1934, (14) thousands more as World War II (15).问题1选项A.forB.toC.withD.on问题2选项A.concerningB.concernC.being concernedD.concerned问题3选项A.undertakeB.undergoC.underplayD.underuse问题4选项A.modelsB.modificationsC.modifiersD.modicum问题5选项A.manifestationsB.manipulationsC.manifestoesD.maneuvers问题6选项A.yawlingB.yawningC.yawingD.yawping问题7选项A.From then onB.From now onC.By nowD.By then问题8选项A.considerableB.considerateC.consideringD.considered问题9选项A.forB.inC.withD.on问题10选项A.On the part ofB.On the basis ofC.On the track ofD.On the verge of问题11选项A.controlB.controllableC.controlledD.controller问题12选项A.toB.forC.onD.in问题13选项A.as forB.as toC.asD.for问题14选项A.acquiringB.requiringC.sustainingD.retaining问题15选项A.realizedB.realizingC.approachingD.approached【答案】第1题:A第2题:D第3题:B第4题:B第5题:D第6题:C第7题:D第8题:A第9题:C第10题:B第11题:A第12题:A第13题:C第14题:A第15题:D【解析】1.【选项释义】A. for对于；因为 B. to给C. with和 D. on在之上【考查点】搭配。【解题思路】substitute作动词时，和for或者with搭配，substitute for sb./sth.表示“代替某人/某物”，substitute B with/by A表示“用A代替B”，空格处后面直接跟了actual fight training（实战训练），故填入for符合搭配，该题选择A项。【干扰项排除】B、D项不符合固定搭配；C项不符合句意。【句意】模拟的目的并不是要完全取代实战训练。2.【选项释义】A. concerning关于；涉及 B. concern担心；关心C. being concerned被关注 D. concerned相关的【考查点】非谓语动词。【解题思路】分析句子可知，空格处跟在名词vehicle的后面，是作vehicle的定语，concern是动词，不能直接跟在vehicle的后面，而vehicle和concern是被动关系，表示被涉及的，所以用concern的过去分词形式，故该题选择D项。【干扰项排除】A项表示主动关系；B、C项是动词，不符合句子语法结构。【句意】模拟的目的不是要完全取代实战训练，而是要让学生彻底熟悉有关的工具。3.【选项释义】A. undertake承担；从事 B. undergo经历，经受C. underplay低调处理；降低的重要性 D. underuse未充分利用【考查点】搭配。【解题思路】根据宾语actual flight training（实际飞行训练）可知，空格处表示“经历”符合动宾搭配，其他三个选项都不符合句意，故该题选择B项。【干扰项排除】A、C、D项不符合动宾搭配。【句意】模拟的目的不是要完全替代实际的战斗训练，而是要在学生进行广泛的和可能危险的实际飞行训练之前彻底熟悉相关的工具。4.【选项释义】A. models模型 B. modifications修改；改进C. modifiers修饰语 D. modicum少量，一点点【考查点】语义逻辑。【解题思路】根据existing和new可推知，new (34)是指在现有的飞机上进行的改进或修改，故该题选择B项符合句子逻辑。【干扰项排除】A、C、D项不符合句子语义逻辑。【句意】模拟也有助于检查和使飞行员熟悉对现有飞机的新改进。5.【选项释义】A. manifestations显示；表明 B. manipulations操纵；控制C. manifestoes宣言 D. maneuvers机动动作；作战演习【考查点】句间逻辑。【解题思路】根据句子可知，冒号后的内容是对空格处进行的解释，根据冒号后的关键信息“机头向上或向下；机翼左高右低或相反”可知，这是对飞机进行动作操作，maneuver指操纵某物的动作，一般是用于作战目的，符合句子语境，故该题选择D项。【干扰项排除】A、C项不符合句意；B项多指需要熟练运用到手的操作，不符合语境。【句意】它们的设计是为了让飞行员在三维空间中模拟简单的飞机动作：机头向上或向下；机翼左高右低或相反。6.【选项释义】A. yawling双桅轻便帆船 B. yawning打哈欠C. yawing偏航 D. yawping叫喊；哭喊【考查点】联系上下文。【解题思路】由to left or right（向左或向右），结合前文提到“在三维空间中模拟简单的飞机动作”可知，空格处表示“偏航”，故该题选择C项符合句意。【干扰项排除】A、B、D项都不符合句子语义逻辑。【句意】向左或向右偏航。7.【选项释义】A. From then on从那时起 B. From now on从现在开始C. By now到目前为止 D. By then到那时候【考查点】联系上下文。【解题思路】根据句子中的had been